Research and Links around Blockchain Technologies


Knowledge Blockchain

This research project applies blockchain technologies to Knowledge Management based on conceptual models. Models are immutably stored, shared and managed on a Knowledge Blockchain.

Knowledge Blockchain at HICSS-51
Project Website

Proof of Existence

Among the most interesting applications for blockchain technologies are existence proofs. The basic idea is to take a hash of any document – e.g. message, photo, certificate – and have it included in a timestamped block of a blockchain. Later on, a Proof of Existence can be conducted by anyone with access to the document and the blockchain, which could be public or private, by re-computing the hash value of the document. If the re-computed hash value matches the one included in the block, the prior existence of the document can be assumed, specifically at the time when the block was mined. If the hash values do not match, nothing can be deduced.

Calculation of SHA-256 values as a basic demonstration on employing hash functions
Proof of Existence at the University of Nicosia
Proof of Existence Services in Bitcoin

more to come


Resources, Block Explorers, Statistics, Full Node Software, Smart Contract Platforms

Bitcoin Project

Bitcoin Developer Resources


Block Explorers

  • Blockchair – comprehensive display of block/transaction data with lots of fields, search capabilities, CSV export, API
  • Smartbit – instant search, also searches data (ASCII) included in transactions with OP_RETURN
  • – supports testnet, Litecoin and others, API
  • – supports testnet, fast and clear design, API
  • Insight – basic blockchain explorer hosted by Trezor, based on Bitcore
  • latest blocks with ASCII-representation of coinbase
  • Yogh Blockchain Reader – clear listing of blocks and transactions in hexadecimal representation


Full Node

  • Bitcoin Core is the Wallet and Full Node from the core developers
  • Bitcore-node is a full node based on Bitcore with API and block explorer
  • Bitnodes – data on full nodes with live map, API

Smart Contract Platforms based on Bitcoin

  • Omni Layer – layer on top of the bitcoin network for distributed exchange and smart property
  • Rootstock / RSK – smart contract execution platform backed by the bitcoin blockchain for smart contracts written in Solidity (compatible to Ethereum)


Resources, Block Explorers, Statistics, Clients, APIs

Ethereum Project

  • Project – Ethereum project
  • White Paper – introduction and concepts
  • Yellow Paper – formal specification for software implementations
  • Research – state of current research projects w.r.t. scaling through sharding etc.
  • Proof of Stake – FAQ on the switch to proof of stake consensus algorithm
  • Sharding – FAQ on sharding as a possible scaling solution

Block Explorers

  • Etherchain – fast and clear design
  • Etherscan – transactions, pending transactions, tokens, API
  • Ethplorer – explorer and tokens monitor, API



  • Go Ethereum / Geth – “official” client written in go
  • Parity – fast, light-weight client
  • Harmony – ethereum network node with web interface, uses EthereumJ
  • EthereumJ – ethereum implementation purely in java
  • cpp-ethereum – client implementation written in c++
  • pyethapp – client implementation written in python
  • ethereumjs-lib – implementation of core functions in javascript


  • Blockcypher – transactions, contracts, events etc.
  • Etherest – API for ethereum contracts
  • Infura – platform and API
  • MyEtherAPI – network, transaction data, by

Smart Contracts

Interesting projects for building private or consortium blockchains for enterprises

Blockchain as a Service


Hyperledger is a project of the Linux Foundation.

Blockchain Platforms

  • Dragonchain – open source project stemming from the Disney private blockchain platform
  • – platform for private blockchains, asset tracking

Blockchain Services

  • IBM – services for private blockchains
  • Deloitte – Rubix platform by Deloitte
  • Samsung SDS – Nexledger platform